In an effort to diminish the appearance of a conflict of interest, he transferred the units—like the rest of his holdings—to a trust operated by his son, Donald Trump Jr. and Trump Organization CFO Allen Weisselberg three weeks before his inauguration, records show.

But assets, like this $35 million apartment, are still for the “exclusive benefit” of Mr. Trump, according to filings dated Jan. 27, 2017 for The Donald J. Trump Revocable Trust, which still uses his social security number for tax purposes.

The four-bedroom condo on the 31st and 32nd floors would be the priciest sale in the building, a luxury high-rise built in 1929 that Mr. Trump renovated and reopened with 120 residences in 2005. It’s over $13 million more than the next most expensive sale there. A penthouse sold in 2005 for $22.91 million, according to property records.

Mr. Trump bought the building, which was formerly the Hotel Delmonico, in 2001.

This isn’t the first time Mr. Trump’s business has tried to sell the unit. The apartment on the top floors of the building reportedly hit the market for the first time shortly before the recession for $51 million. It’s undergone a series of price cuts and come on and off the market every couple of years since, most recently selling for $35 million before Mr. Trump took it off the market again in March 2016.

A listing for the property calls it a “showplace residence (that) is awaiting the most discerning buyer.”

The unit, serviced by a private elevator, has been finished with solid oak floors, Italian brass doorknobs and custom mouldings. The entry gallery has crystal sconces and a chandelier, according to the listing with Trump International Realty.

It also appears to be one of the most expensive units on the market in a New York City Trump-branded building, according to listing website CityRealty.

Trump International Realty referred questions to the Trump Organization, a spokeswoman for which was not immediately available to comment.